The present invention relates to ball joints, such as ball joints used in automotive suspension systems.
There has been considerable activity towards the development of ball joints that are inexpensive, light in weight, and reliable. Sugiyama U.S. Pat. 4,435,101 and Broszak U.S. Pat. No. 5,152,628 disclose ball joints utilizing polymeric housings that are typically injection molded. The following patents disclose various methods for holding a ball joint socket to a ball joint housing, including bonding, threading, and snap-locking: U.S. Pat. No. 5,782,573 (Dorr), U.S. Pat. No. 5,417,512 (Chamberlin), U.S. Pat. No. 4,679,958 (Mizusawa), U.S. Pat. No. 4,116,504 (Cass); DE 196 25 351; EP O 163 296; and GB 1 580 182.
In spite of this earlier work, a need exists for an improved ball joint that secures the socket and the rod to the housing in a simple, high-strength manner.
The ball joint illustrated in the drawings includes a socket that is snap-locked to a housing by complementary teeth and cavities. The crests of the teeth are smoothly curved with a radius larger than 0.5 millimeter, and the teeth of the housing and the socket are arranged at respective taper angles oriented to facilitate insertion.
The illustrated ball joint is assembled by first inserting the ball into the socket, and then snap-locking the socket into the housing by forcing the teeth of the housing and socket past one another to create the desired engagement. If desired, a suitable adhesive can be used to supplement the mechanical engagement described above.
One of the illustrated ball joints described below includes a recess that defines an undulating surface. The recess receives the rod with the undulating surface facing the rod. The space between the undulating surface and the rod is filled with a suitable adhesive, and the adhesive secures firmly to the rod and reacts against the converging and diverging portions of the undulating surface to resist compressive and tensile loading.
The foregoing paragraphs have been provided by way of introduction, and it is not intended to narrow the scope of the following claims.